Should I refinance?

First thing is first, 4.5% on a 15 year mortgage is far too high. 15 year rates are in the mid-3's at this time. Given that you secure a competetive rate such as what I have mentioned here, I would say that it is very likely to be a valid savings, especially if you intend to cash flow your rental income when you decide to go down that path. You will not only gain more equity faster in a 15yr setting, but your rate will be much lower than you have now - therefore allowing you the option to overpay on your mortgage and build even more equity in less time.

It will depend on your credit and value of your home. Right now , rates are down about 4% and under. A .25% rate deduction that you are quoted is probably not enough to make a difference even with the 15 yr terms.. Please email me your fico number and the approx value of your home to lindaforloans@live.com

In today's market, 4.5% for a 15 year loan is way too high. Second, you should not be paying $3500 in closing costs on a $76,000 loan. Based on what you provided, you are thinking of paying $3500 to lower your rate by a 1/4% and only save 9 years of payments, is probably not the wisest choice. You should be seeing a rate in the high 3's for a 15 year, and not more than $1500 - $2000 in closing costs, plus the appraisal. I would encourage you to look for a local Mortgage Banker or Mortgage Broker and avoid the big banks. Another option is to see how much extra you would need to pay each month to make your existing loan a 15 year loan and save the $3500, especially since you indicated you may not be in the home for more thatn another 5 years or so. Although I do not lend in IA, I would be happy to discuss this concept with you.